In recent years, an electric vehicle which can use power of a power supply external to the vehicle (external power supply) to charge a main battery which stores power for operating a motor for traveling (what is called plug-in vehicle) is in practical use. With respect to such plug-in vehicles, for example, Japanese Patent Laying-Open No. 2009-225587 (PTL 1) discloses a plug-in vehicle which includes, apart from a main converter which is provided on an electric path between a main battery and a motor for traveling and capable of charging an auxiliary machinery battery with the power of the main battery, a sub-converter which is provided on an electric path between the main battery and an external power supply and capable of directly charging the auxiliary machinery battery with the power of the external battery.